This application is a continuation of international application Ser. No. PCT/FR89/00641, filed Dec. 11, 1989, which is designated the United States, now abandoned, such application basing its priority under 35 U.S.C. .sctn.119 on French patent application, Ser. No. 88/16311, filed Dec. 12, 1988.
The present invention relates to a ligating assembly for endoscopic surgery.
Endoscopic surgery is a technique which is typically used for intra-abdominal surgery, where the surgeon operates without making an incision in the abdominal wall by passing instruments inside trocar tubes that pass through said abdominal wall. Manipulations are observed via an endoscope inserted in one of the trocar tubes, with the abdominal cavity being previously distended by insufflation of a gas such as CO.sub.2 in order to allow manipulation inside the abdominal cavity to be observed.
It is thus possible to install ligatures intra-abdominally. This manipulation consists in passing a binding means around an organ or some tissue and then in knotting and tightening the binding means. Ligatures can thus be installed for closing internal wounds, or around adhesions before or after resection, etc.
In the state of the art, these ligatures are installed in several different ways.
The most elementary technique consists in performing tieing entirely within the body by manipulating the thread while actually inside the abdominal cavity.
In a second technique, a loop is prepared in advance with a slip knot, the loop is then threaded inside the trocar tubes, then the loop is placed around the portion to be ligated, and is tightened by pulling on the slip knot, after which the remaining end of the thread is cut off.
Naturally, this technique can only be applied when it is possible to pass the loop over the part to be ligated, i.e. when said part is constituted by a projecting portion of an organ or of tissue (typical of an adhesion for resection, where it is desired to ligature the remaining portion in order to prevent any infusion or alcohol.
The third technique, referred to as "ligature with extracorporal tieing", consists in inserting a thread in trocar tubes, passing the free end of the thread around the part to be ligated, reinserting said free end in the trocar tube in order to bring it back out from the abdominal cavity at the other end of the trocar tube, tieing a slip knot with said free end around the portion of the thread penetrating into the trocar tube, inserting the resulting loop into the trocar tube so as to cause it to leave via the other end inside the abdominal cavity in the vicinity of the part to be ligated, tightening the knot finally, and then cutting off the remaining end of the thread.
This technique is naturally lengthly and difficult to perform, but it is the only technique which is well adapted to ligating parts over which it is not possible to pass a preconstituted slip knot, typically ligatures which are put into place prior to resection at the root of an adhesion in order to prevent any subsequent hemorrhage at that point, or ligatures for vessels or ducts.
Preferred embodiments of the invention provide a ligating assembly which is quick and easy to use, and which can be used regardless of the shape of the part to be ligated, thereby avoiding the difficulties relating to the extra-corporal tieing technique.
To this end, the present invention provides a ligating assembly comprising a trocar, and a one-piece element constituted by a body fittable in the end of said trocar tube, and by a thread extending from said body and constituting binding means, the body including a threading channel receiving the free end of the thread at one of its end and opening out to the inside of the trocar tube at its other end, the thread and the channel being provided with tightening means for retaining the thread in position once it has been inserted at least partially into the channel.
Thus, essentially, the tieing operation (prior tieing of a slip knot, or extra-corporal tieing) is replaced by a threading and tightening operation which is always easier to perform.
Preferably, the tightening means comprise co-operating notched regions formed on the outside surface of the thread and on the inside surface of the threading channel.
In an advantageous embodiment, the ligating assembly also comprises grasping and pulling means insertable inside the trocar tube for grasping and pulling the free end of the thread once threaded through the threading channel and projecting therefrom into the trocar tube, thereby enabling the ligature to be tightened by pulling on said free end.
As a result, once the free end of the thread has been inserted far enough into the threading channel, the surgeon can tighten the binding without any need to continue pushing said free end into the threading channel. It suffices to actuate a simple movement of the grasping and pulling means in order to tighten the ligature fully.
Advantageously, these grasping and pulling means comprise, for example, two telescopic elements axially moveable relative to each other, one of the elements being provided with jaws for grasping and clamping onto the free end of the thread, the two elements being such that relative axial movement thereof causes the jaws to move towards each other and clamp onto the free end of the thread, with simultaneous axial movement of the two elements then pulling said free end and consequently tightening the ligature.
The ligating assembly may also include cutting-off means insertable into the trocar tube for cutting off the free end of the thread after it has been pulled; these cutting-off means advantageously comprise, for example, a guillotine which is moveable inside the trocar tube, transverse guide means for guiding the guillotine, and actuator means for driving the guillotine in transverse motion after the free end of the thread has been fully tightened.
Thus, in addition to installing and tightening the ligature, the free end thereof projecting outside the body of the one-piece element is cut-off quickly and completely safely. The cutting operation takes place inside the trocar tubes, thereby avoiding the need to use a separate cutting instrument inserted via another trocar tube, as has always been required in the past, and thus requiring observation via an endoscope in order to be put into place and actuated.